That is all well and good - except that these galaxies might not be our satellites at all.

Observations in 2006 by the Hubble Space Telescope showed that these two dwarfs are crawling across the sky at a little shy of a millionth of a degree per year. That might not sound speedy, but the galaxies are more than 150,000 light years away, so it translates to a velocity of more than 100 ...

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